The bypass angioplasty revascularization investigaiton (BARI) is a prospective multicenter, randomized clinical trial of percutaneous transluminal coronary angioplasty (PTCA) compared to coronary artery bypass surgery (CABG). Patients with Canadian Class III or IV angina, and patients who are status-post myocardial infarction with suitable multivessel coronary artery disease will be randomized to receive PTCA or CABG. A 2 year recruitment and 5 year follow-up period will be required. The major endpoints for the trial will be mortality and myocardial infarction. In order to detect a difference between the interventions 2,000 patients will be randomized. Other outcomes which will be studied for these intervention inclued: 1) relief of angina, 2) rest and exercise left ventricular function, 3) completeness of revascularization, 4) recurrence rate, 5) corssover rate, 6) cost, 7) memory and cognitive abilities, and 8) quality of life. The date analysis will also focus on several important subsets including those patients: 1) status-post recent myocardial infarction, 2) age over 65 years, 3) proximal left anteriaor descending artery stenosis, 4) unstable angina 5) chronic total occlusion, and 6) imparied left ventricular function. The results of this trial are expected to help delineate the optimal application of the PTCA and CABG interventional strategies.